SheetImagePicker/SheetImagePickerTest/ViewController.swift

//
//  ViewController.swift
//  SheetImagePickerTest
//
//  Created by Shadowfacts on 9/23/19.
//  Copyright © 2019 Shadowfacts. All rights reserved.
//

import UIKit
import SheetImagePicker

class ViewController: UIViewController {
    
    var sheet: SheetContainerViewController!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        view.backgroundColor = .green
    }

    @IBAction func plainPressed(_ sender: Any) {
        let content = UIViewController()
        content.view.translatesAutoresizingMaskIntoConstraints = false
        let blurEffect = UIBlurEffect(style: .systemChromeMaterial)
        let blurView = UIVisualEffectView(effect: blurEffect)
        blurView.translatesAutoresizingMaskIntoConstraints = false
        let label = UILabel()
        label.translatesAutoresizingMaskIntoConstraints = false
        label.text = "Hello, sheet!"
        blurView.contentView.addSubview(label)
        content.view.addSubview(blurView)
        NSLayoutConstraint.activate([
            content.view.leadingAnchor.constraint(equalTo: blurView.contentView.leadingAnchor),
            content.view.trailingAnchor.constraint(equalTo: blurView.contentView.trailingAnchor),
            content.view.topAnchor.constraint(equalTo: blurView.contentView.topAnchor),
            content.view.bottomAnchor.constraint(equalTo: blurView.contentView.bottomAnchor),
            label.centerXAnchor.constraint(equalTo: blurView.contentView.centerXAnchor),
            label.centerYAnchor.constraint(equalTo: blurView.contentView.centerYAnchor)
        ])

        sheet = SheetContainerViewController(content: content)
        sheet.delegate = self
        sheet.detents = [.bottom, .middle, .top]
        
        present(sheet, animated: true)
    }
    
    @IBAction func tablePressed(_ sender: Any) {
        let content = ContentTableViewController()
        content.view.translatesAutoresizingMaskIntoConstraints = false
        content.view.layer.masksToBounds = true
        content.view.layer.cornerRadius = view.bounds.width * 0.02
        
        sheet = SheetContainerViewController(content: content)
        sheet.delegate = self
        sheet.detents = [.bottom, .middle, .top]
        
        present(sheet, animated: true)
    }
    
    @IBAction func navPressed(_ sender: Any) {
        let root = UIViewController()
        root.view.backgroundColor = .systemBackground
        let label = UILabel()
        label.text = "Root VC"
        label.translatesAutoresizingMaskIntoConstraints = false
        root.view.addSubview(label)
        NSLayoutConstraint.activate([
            label.centerXAnchor.constraint(equalTo: root.view.centerXAnchor),
            label.centerYAnchor.constraint(equalTo: root.view.centerYAnchor)
        ])
        
        let nav = UINavigationController(rootViewController: root)
        nav.view.translatesAutoresizingMaskIntoConstraints = false
        nav.view.layer.masksToBounds = true
        nav.view.layer.cornerRadius = view.bounds.width * 0.02

        sheet = SheetContainerViewController(content: nav)
        sheet.delegate = self
        sheet.detents = [.bottom, .middle, .top]
        
        present(sheet, animated: true)
    }
    
    @IBAction func navTablePressed(_ sender: Any) {
        let table = ContentTableViewController()
        
        let nav = UINavigationController(rootViewController: table)
        nav.delegate = self
        nav.view.translatesAutoresizingMaskIntoConstraints = false
        nav.view.layer.masksToBounds = true
        nav.view.layer.cornerRadius = view.bounds.width * 0.02
        
        sheet = SheetContainerViewController(content: nav)
        sheet.delegate = self
        sheet.detents = [.bottom, .middle, .top]
        
        present(sheet, animated: true)
    }
}

extension ViewController: SheetContainerViewControllerDelegate {
    func sheetContainer(_ sheetContainer: SheetContainerViewController, willSnapToDetent detent: Detent) -> Bool {
        if detent == .bottom {
            sheetContainer.dismiss(animated: true)
            return false
        }
        return true
    }
    func sheetContainerContentScrollView(_ sheetContainer: SheetContainerViewController) -> UIScrollView? {
        if let navController = sheetContainer.content as? UINavigationController, let scrollView = navController.visibleViewController?.view as? UIScrollView {
            return scrollView
        } else {
            return nil
        }
    }
    func sheetContainer(_ sheetContainer: SheetContainerViewController, topContentOffsetForScrollView scrollView: UIScrollView) -> CGFloat {
        if let navController = sheetContainer.content as? UINavigationController, navController.visibleViewController?.view is UIScrollView {
            return -navController.navigationBar.bounds.height
        } else {
            return 0
        }
    }
}

extension ViewController: UINavigationControllerDelegate {
    func navigationController(_ navigationController: UINavigationController, didShow viewController: UIViewController, animated: Bool) {
        sheet.contentScrollViewChanged()
    }
}